1. Technical Field
The present disclosure generally relates to infrared detectors.
2. Description of Related Art
Infrared detectors are used to detect infrared which are not visible to humans. Infrared detectors are used in the medical field, mine detecting field, military affairs, and everyday life.
Infrared detectors can be divided into active infrared detectors and passive infrared detectors according to their working principles and structures. An active infrared detector includes an infrared producing device, an infrared receiving device, and a warning device. When humans, animals or other things pass through the infrared produced by the infrared producing device, the energy of the infrared will change, and the infrared receive device can detect a change of the energy and activate the warning device. Passive infrared detectors do not produce infrared. Instead, the passive infrared detector detects the energy of the infrared signals when infrared irradiates the device. An infrared detector, whether active or passive, should include a detecting element sensitive to infrared. The conventional detecting element uses the photoelectric effect to change infrared into electric signals, and the infrared signals are detected by detecting the electric signals. However, due to the low efficiency of the photoelectric effect, the infrared detected must have enough intensity. As such, the conventional infrared detectors have low sensitivity.
What is needed, therefore, is an infrared detector based on carbon nanotubes that can overcome the above-described shortcomings.